Imitating nature leads to a better catalyst

An inexpensive and scalable composite catalyst that is said to outperform platinum for oxygen reduction in metal-air batteries and fuel cells has been developed by a research team led by professor Jaephil Cho from Ulsan National Institute for Science and Technology (Ulsan, South Korea; www.unist.ac.kr). The team includes people from Pohang Accelerator Laboratory (Pohang, South Korea), Los Alamos National Laboratory (Los Alamos, N.M.), Georgia Institute of Technology (Atlanta, Ga.) and SRM University (Kattankulathur, India). Polarization due to the oxygen-reduction reaction contributes significantly to the energy efficiency of fuel cells and metal-air batteries. Although Pt and its alloys are the most efficient catalysts for activation of the O=O bond, their application is limited by high costs and scarce reserves. The new catalyst — iron phthalocyanine (FePc), with an axial ligand anchored on single-walled carbon nanotubes (CNTs) — has shown a higher electrocatalytic activity for oxygen reduction than traditional Pt on carbon catalysts. The catalyst has shown exceptional durability and electrocatalytic activity in alkaline media. It has also achieved a long cycle life, attaining more than 1,000 cycles in a durability test. The…